174 SCHOOL ENTOMOLOGY 



the fumigating box. Place the carbon bisulphide in an 

 open dish near the top of the box. Use at the rate of 

 about one ounce to ten cubic feet of space. Be sure to 

 have the temperature at least 65 to 70 F. Keep fire 

 away as the material is explosive. Repeat the fumigation 

 once every month or six weeks during the warm weather, 

 or whenever any signs of the injurious insects appear. 



As protection against mold and similar troubles be sure 

 to have the insects reasonably dry before they are closed 

 up tightly and permanently, then keep the collection in a 

 dry place. Insect boxes must be handled with care at 

 all times to avoid breaking legs, antennae and other deli- 

 cate structures from the specimens by jarring. 



111. Microscopes. In addition to the equipment neces- 

 sary for collecting and mounting insects a little more is 

 required for their study. Of this, the most important 

 part is the microscope or lens. The most useful lens will 

 be a hand lens magnifying about twenty diameters. Pro- 

 vided with such a lens the student will seldom need a 

 compound microscope. A good plan for a beginning 

 course in entomology is for the class to be furnished with 

 two or three compound microscopes and for each mem- 

 ber of the class to have his own hand lens. 



